UART mikroC 16F877a interfacing

[varunme]

in the below code , it is to display "start" as soon as the com port / uC is connected isnt it ?, but it isnt and whenever the UART1_Write_Text is used, then some problem is there, but the program is echoing the character i sent

compiler mikroC and using hyperterminal

char uart_rd;

void main() {
  ADCON1 |= 0x0F;                 // Configure AN pins as digital
  CMCON  |= 7;                    // Disable comparators
  
  UART1_Init(19200);               // Initialize UART1 module at 9600 bps
  Delay_ms(100);                  // Wait for UART 1module to stabilize
  UART1_Write_Text("Start");
  UART1_Write(13);
  UART1_Write(10);
  while (1) {                     // Endless loop
    if (UART1_Data_Ready()) {     // If data is received,
      uart_rd = UART1_Read();     //   read the received data,
      UART1_Write(uart_rd);       //   and send data via UART1
    }
  }
}

 

[bigdogguru]

The recommend/available BAUD rate depends largely on Fosc or crystal frequency.

What is your Fosc/Crystal frequency and have you set the frequency in the MikroC IDE?

In selecting the BAUD rate you must attempt to keep the %Error between the Desired and Obtainable BAUD Rates as close to zero as possible.

These %Error rates can be calculated by hand or obtain in the PIC16F87XA Datasheet, Table: 10-3 and 10-4:



%Error over 1% are increasingly prone to transmission/receiving problems.

BigDog

 

[xpress_embedo]

UART1_Init(19200);
Means that you are using 19200 Baud Rate

UART1_Write_Text("Start");
//Means you are sending the "Start" to the Serial Pins of the Controller

UART1_Write(13);
//Means you are using Carriage return in short "ENTER" key of keyboard whose ASCII value is 13

UART1_Write(10);
//Means you are using Line Feed whose ASCII value is 10
//Search Google to see the difference b/w Line Feed and Carriage Return


if (UART1_Data_Ready()
//The above Statement check whether u are receiving any data from the serial pins or not
//If you are getting some data then following commands will get executed

uart_rd = UART1_Read(); // read the received data,
//Whatever character u received is stored in the uart_rd variable

UART1_Write(uart_rd); // and send data via UART1
//And What ever variable you read is sent to the Serial PORT Again

Open Hyper-Terminal in Windows
Connect the Controller with appropriate logic conversion(MAX232) with the serial port of computer
then POWER-ON the Controller

You will get a "Start" on the hyperterminal 'don't forget to set the baud rate of PC's Hyper-Termianl
after that
whatever you type on the Hyper-Terminal you will be able to see that..


Hope this explanation helps u


Regards
Arun Sharma

 

[varunme]

UART1_Init(19200);
Means that you are using 19200 Baud Rate

UART1_Write_Text("Start");
//Means you are sending the "Start" to the Serial Pins of the Controller

UART1_Write(13);
//Means you are using Carriage return in short "ENTER" key of keyboard whose ASCII value is 13

UART1_Write(10);
//Means you are using Line Feed whose ASCII value is 10
//Search Google to see the difference b/w Line Feed and Carriage Return


if (UART1_Data_Ready()
//The above Statement check whether u are receiving any data from the serial pins or not
//If you are getting some data then following commands will get executed

uart_rd = UART1_Read(); // read the received data,
//Whatever character u received is stored in the uart_rd variable

UART1_Write(uart_rd); // and send data via UART1
//And What ever variable you read is sent to the Serial PORT Again

Open Hyper-Terminal in Windows
Connect the Controller with appropriate logic conversion(MAX232) with the serial port of computer
then POWER-ON the Controller

You will get a "Start" on the hyperterminal 'don't forget to set the baud rate of PC's Hyper-Termianl
after that
whatever you type on the Hyper-Terminal you will be able to see that..


Hope this explanation helps u


Regards
Arun Sharma

whenever the UART1_Write_Text is used, then some problem is there, but the program is echoing the character i sent

The usage of UART1_Write_Text is the problem, not getting the start message and whenever i use UART1_Write_Text , some problem in sending

 

[xpress_embedo]

First open Hyper-Terminal

Then Select Baud Rate
and after that
Power-ON your Micro-Controller board...

Few months back...
When i have started using pic
i am using mikroC compiler and at that time i had just copy paste that code available in help documentation of mikroc
Which is exactly your ones..

means u to have copy the code from help documentation

for me it works..

so the problem is from ur end not from compiler end

 

[varunme]

yess......

 

[bigdogguru]

I prefer PuTTY over Hyperterminal.

PuTTY Download Page

I find it a lot more versatile and supports many more features including SSH

The newline or return characters maybe cause some issue:

Try

 UART1_Write_Text("Start\n\r");

Or

 UART1_Write_Text("Start\n");

Instead Of:

 UART1_Write_Text("Start");
 UART1_Write(13);
 UART1_Write(10);

BigDog

 

[varunme]

in serial communication with C#, will these produce problems ?

---------- Post added at 10:11 ---------- Previous post was at 10:09 ----------

I prefer PuTTY over Hyperterminal.

PuTTY Download Page

I find it a lot more versatile and supports many more features including SSH

The newline or return characters maybe cause some issue:

Try

 UART1_Write_Text("Start\n\r");

Or

 UART1_Write_Text("Start\n");

Instead Of:

 UART1_Write_Text("Start");
 UART1_Write(13);
 UART1_Write(10);

BigDog

After the starting point

 UART1_Write_Text("Start\n");

 UART1_Write_Text("Start\n\r");

may solve the UART1_Write_Text issue ?

 

[xpress_embedo]

in serial communication with C#, will these produce problems ?

No if you use everything properly then no problem will occur...

Have u solved ur problem..
It working now... or not..

 

[varunme]

yes its working,
Thanks dear,

 

[xpress_embedo]

And Download Putty...
as BigDogGuru Suggested..

It much better than Hyper-Terminal of Windows
And One thing more
You may not find Hyper-Terminal in windows 7
in that case use putty

---------- Post added at 22:49 ---------- Previous post was at 22:47 ----------

yes its working,
Thanks dear,

Your Welcome

 

[varunme]

yes,
i use winXP in laptop for embedded
and desktop win7, but hyperterminal can be ported to win7 also,

But i will download putty today, to lessen by headache, thanks for you both.

 

[varunme]

can we use something like the below in mikroC ?

char uart_rd;

void main() {
  ADCON1 |= 0x0F;                 // Configure AN pins as digital
  CMCON  |= 7;                    // Disable comparators

  UART1_Init(9600);               // Initialize UART1 module at 9600 bps
  Delay_ms(100);                  // Wait for UART 1module to stabilize
  UART1_Write_Text("Start");
  UART1_Write(13);
  UART1_Write(10);
  while (1) {                     // Endless loop
    if (UART1_Data_Ready()) {  
    uart_rd = UART1_Read(); //   read the received data,
    switch (uart_rd )       // If data is received,
    {
     case 1:
     portb.f1=1;
     case 2:
      portb.f2=1;
     
    
    }

     // UART1_Write(uart_rd);       //   and send data via UART1
    }
  }
}

 

[xpress_embedo]

can we use something like the below in mikroC ?

Code:

char uart_rd;

void main() {
ADCON1 |= 0x0F; // Configure AN pins as digital
CMCON |= 7; // Disable comparators

UART1_Init(9600); // Initialize UART1 module at 9600 bps
Delay_ms(100); // Wait for UART 1module to stabilize
UART1_Write_Text("Start");
UART1_Write(13);
UART1_Write(10);
while (1) { // Endless loop
if (UART1_Data_Ready()) {
uart_rd = UART1_Read(); // read the received data,
switch (uart_rd ) // If data is received,
{
case 1:
portb.f1=1;
case 2:
portb.f2=1;


}

// UART1_Write(uart_rd); // and send data via UART1
}
}
}

Yes we can,
But what is this PORTB.F1

I don't understand this..

 

[varunme]

first bit of portb

 

[xpress_embedo]

Yes it will work..
But Make sure that uart_rd is a single byte character..

 

[varunme]

But itsnt working , this is my final code

char uart_rd;

void main() {
trisb=0;
portb=0;
  ADCON1 |= 0x0F;                 // Configure AN pins as digital
  CMCON  |= 7;                    // Disable comparators

  UART1_Init(9600);               // Initialize UART1 module at 9600 bps
  Delay_ms(100);                  // Wait for UART 1module to stabilize
  UART1_Write_Text("Start");
  UART1_Write(13);
  UART1_Write(10);
  while (1) {                     // Endless loop
    if (UART1_Data_Ready()) {  
    uart_rd = UART1_Read(); //   read the received data,
    switch (uart_rd )       // If data is received,
    {
     case 1:
     portb.f1=1;
     delay_ms(500);
     case 2:
      portb.f2=1;
      delay_ms(500);
     
    
    }

     // UART1_Write(uart_rd);       //   and send data via UART1
    }
  }
}

 

[xpress_embedo]

WIll be Describe what happens....


If you Press 1 in Hyperterminal, then your first Case statement will gets executed..
and The first pin of PORTB gets high

I am not much aware with the Mikro C sytax..

But there must be a break after every case

case 1:
     portb.f1=1;
     delay_ms(500);
      break;
     case 2:
      portb.f2=1;
      delay_ms(500);
      break;

Hope this Helps